Goals: The Wide-field Infrared Survey Explorer (WISE) will provide a vast storehouse of knowledge about the solar system, the Milky Way and the Universe. Among the objects WISE plans to study are asteroids, the coolest and dimmest stars, and the most luminous galaxies.
Accomplishments: WISE scanned the entire celestial sky in infrared light about 1.5 times. It captured more than 2.7 million images of objects in space, ranging from faraway galaxies to asteroids and comets close to Earth. After completing its prime science mission, the spacecraft ran out of the frozen coolant that keeps its instrumentation cold. However, two of its four infrared cameras remained operational. These two channels were still useful for asteroid hunting, so NASA extended the NEOWISE portion of the WISE mission by four months, with the primary purpose of hunting for more asteroids and comets, and to finish one complete scan of the main asteroid belt. The spacecraft was then placed in hibernation in case another science opportunity arose.
WISE was revived with the goal of discovering and characterizing near-Earth objects (NEOs). NASA anticipates WISE will use its 40-cm (16-inch) telescope and infrared cameras to discover about 150 previously unknown NEOs and characterize the size, albedo and thermal properties of about 2,000 others.